Synergistic additive mixtures for fuels



3,0353% Patented May 22, 1962 [ice 3 035 906 SYNERGISTIC AnnITivEr nXTUREs ron FUELS James B. Hinkamp, Birmingham, Mich, asszgnor to Ethyl Corporation, New York, N.Y., a corporation of Delaware N Drawing. Filed May 28, 1958, Ser. No. 738,284 6 Claims. (Cl. 44-66) New non-corrosive gasoline additives having strong anti-icing properties are among the objects of this invention.

The additives are the B-hydroxyethyl ethylenediamine amides of oleic acid (henceforth MPA) mixed with methyl phosphates. As little as 0.5 percent by weight of MPA makes the mixtures non-corrosive to ferrous metals when water is present and even when storage temperatures are high (90-120 F.). Absent MPA, the phosphates corrode ferrous metals under these conditions.

Because MPA itself is non-corrosive, there is no necessary upper limit on the amount used with the phosphates. Costwise, up to about 75 percent of MPA in the mixture is very good.

. The methyl phosphates have the formula R and R being methyl, phenyl, tolyl or xylyl. Of these compounds trimethyl phosphate is most easily hydrolyzed. Therefore, when water seeps or otherwise gets into iron drums or cans in which it is stored, there is drastic corrosion. Yet strangely, this does not happen when MPA is present. Instead, metal corrosion is sharply reduced.

Much harder to hydrolyze are the other above phosphates-cg, dimethyl xylyl phosphate, methyl ditolyl phosphate, etc. But to the extent they do hydrolyze under rough treatment, there is a commercial problem. Certain mixtures of these phosphates are commerciallyused ignition control compounds for motor fuel and their metal shipping drums are often exposed to rain, high temperatures, etc. Result if the water gets inside: Hydrolysis of the phosphate and consequent corrosion. But conjoint use of MPA squelches and problem.

Also non-corrosive are hydrocarbon solutions of these MFA-phosphate mixes. For instance, gasoline stock or blending solutions of high phosphate content (e.g., 10-20 weight percent) containing MPA (0.5 weight percent or more based on the phosphate) do not corrode iron or steel tanks, pipelines, etc., though water be present and temperatures high. More dilute gasoline solutions are likewise non-corrosive even when stored for years over water.

Another big feature of gasoline-phosphate-MPA systems is their potent anti-icing properties. They quash the frequent stalling of automotive, marine, stationary and airplane engines normally sufiered during running mostly at idlein cool, moist weather. This feature exists in gasoline containing (by weight) about 75-550 parts per million (p.p.m.) of the above phosphates and about -200 p.p.m. of MPA, the total phosphate-MFA content being at least 130 p.p.m.

Synergistic anti-icing efiects exist in the above fuels with MPA and the phosphates which have up to 2 methyl ester groups-dimethyl phenyl, dimethyl tolyl, dimethyl xylyl, methyl diphenyl, methyl ditolyl, and methyl dixylyl phosphates. Mixtures of these phosphates are likewise synergistic with MPA. A preferred synergistic fuelof this invention is gasoline containing about 15-100 p.p.m.

of MPA and about 200-450 p.p.m. of the phosphates having up to 2 methyl ester groups, especially a mixture composed predominantly of dimethyl xylyl phosphate and methyl dixylyl phosphate, about four-fifths of the phosphate mixture being the dimethyl compound.

These anti-corrosion and anti-stalling properties persist in the presence or absence of other fuel additives. Thus, the fuel may be leaded. It may contain other antiknocke.g., methylcyclopentadienyl manganese tricarbonyl, etc. Antioxidants, metal deactivators, dyes, aromatic solvents (e.g., xylene, etc.) and the like may be present. In every case, the benefits of this invention are fully realized.

On top of all this, my MFA-phosphate mixtures cause no problems in use. They are liquids that are easy to blend with fuel even in the cold. They do not harm fuel stability. They are perfectly engine-inductible. And they form no harmful engine deposits.

MPA and some of the phosphates are now being sold. MPA is made by heating oleic acid with p-hydroxyethyl ethylenediamine under azeotropic conditions to form the imidazoline This is then treated with water to form MPA, i.e., a mixture of the amides i C17H33O-NHC:H4NHC2H40H It is best to mix these amides with 30-40 percent aromatics of the xylene range, 3-8 percent butanol (lowers freezing point) and about 4 percent water (prevents jelling in the cold and keeps the imidazoline hydrolyzed). When so formulated, MPA is an amber liquid. Typical properties: gravity, API (ASTM D-287) 20-25; pour point, F. (ASTM D-97), ca. 15; viscosity at 100 F., SSU (ASTM D-445 and 446), ca. 260; total base number, mg. KOH/ gram 75-85.

The phosphates can be made by reacting POCl with the right amount of phenol, cresol, xylenol and/or methanol. HCl is given off and the ester formed. Details for making trirnethyl phosphate are well known and described in the literature. The dimethyl aryl phosphates are best made by first reacting (mole per mole the phenol in question with POCl Use is made of AlCl as catalyst0.25-3.0 mole percent based on the phenol. Temperature: tiff-130 C. The phenol should be fed a little at a time to the POCI The producta phenyl phosphorodichloridate-is then added slowly to methanol (at least 4 moles per mole of POCl first used). Keep the mixture at 15-60 C. until all the product is added. Then, quench with water and distill olf the ester from the organic phase at reduced pressure (dimethyl phenyl phosphate 114 C. at 2 mm; dimethyl tolyl phosphate 113-115 C. at 1 mm.; dimethyl xylyl phosphate 113- 115 C. at 0.5 mm). The methyl diaryl phosphates are made the same way except that the ratios are changed (phenol: POCl is 2:1 and at least two moles of methanol are used per mole of P0Cl The end products distill at slightly higher temperatures than the dimethyl aryl phosphates. All of these phosphates are clear white or light yellow liquids.

To make my MFA-phosphate mixtures, apt amounts of each are blended in a tank, can or other vessel. A little stirring or shaking helps. No special precautions need be taken.

My fuels can be made by blending the correct amount short times.

of one of my MPA-pnosphate blends with the gasoline. If desired, a fuel concentrate can first be made for use in later fuel blending steps. Then again my fuels can be made by blending first one and then the other of my additives with the gasoline. As before, the correct amount of each can be used in the first instance or a fuel concentrate can be formed and cut with more gasoline to the desired level. Other additives, if used, can be blended before, during or after the above fuel blending steps.

In the examples below, parts and percents are by weight.

EXAMPLE I Mixed are 99.5 parts of methyl dixylyl phosphate and 0.5 parts (0.5 percent) of MPA. The liquid is non-corrosive to ferrous metals when placed in contact with water.

EXAMPLE II To 75 parts of MPA is added 25 parts of dimethyl phenyl phosphate. They are mixed. The liquid composed of 75 percent MPA is not corrosive to strips of iron when resting on a water layer and held at 120 F.

for days on end.

EXAMPLE III Mixed are 90 parts of trimethyl phosphate and 10 parts (10 percent) of MPA. The liquid product is much less corrosive of steel drums when water is present than is the pure phosphate.

EXAMPLE IV A 50 percent MFA-methyl ditolyl phosphate mixturemade from 50 parts of eachand also 10 and percent gasoline solutions of this mixture are found non-corrosive to ferrous metals in the presence of water.

EXAMPLE V Stirred with 990 parts of mixed methyl tolyl phosphates (dfi 1.113; n 1.496) is 10 parts of MPA (1 percent).

The liquid product is non-corrosive to iron drums in which Water has gathered.

EXAMPLE VI With 10 parts of aviation fuel containing 4.6 ml./ gal. of tetraethyllead (TEL) as l-T Mix is added 200 parts (200 ppm.) of MPA. Next is added 75 parts (75 ppm.) of trimethyl phosphate. The mixture is stirred. The finished fuel is non-corrosive to ferrous metals and has good de-icer quality. NOTE.l-T Mix is made up mostly of TEL and l theory of ethylene dibromide. A theory is 2 halide atoms per lead atom.

Other examples vis-a-vis engine test Work are given below.

The test set up was a 1953 car engine drawing its air from outdoors through an ice tower. The carburetor had a water-jacketed throttle body through which ice water was passed to keep the throttle blade cold. The

intake m'r temperature was controlled by blending inside All tests were run when outside temperatures were below 40 F. In this way, icing md stalling were obtained in Test details:

In the table are the tests results:

T able-Effect of Additive-s on Engine Stalling Average Increase in Stall Time, Percent No. A dditive p.p.m.

Methyl xylyl phosphate 1 220 13 do 440 57 1 Dirnethyl xylyl phosphate: methyl dixylyl phosphate ca. :20 wt. percent.

Note from items 5 and 6 that my fuels were synergistic. By the same test method, 1.5 volume percent of isopropanola widely used deicer-gave only a 45 percent increase in stall time. This further shows the great antistalling strength of my fuels.

I claim:

1. A. fuel additive composition consisting essentially of a phosphate having the formula CH30P wherein R and R are selected from the group consisting of methyl, phenyl, tolyl and xylyl, and the p-hydroxyethyl ethylenediamine amides of oleic acid; said additive containing from 0.5 to 75' percent by weight of said amides.

2. Gasoline containing by Weight about 75-550 parts per million of a phosphate having the formula wherein R and R are selected from the group consisting of methyl, phenyl, tolyl and xylyl, and about 15-200 parts per million of the ,B-hydroxyethyl ethylenediamine amides of oleic acid, the total content of said phosphate and amides being at least parts per million.

3. Gasoline containing by weight about 200-450 parts per million of a phosphate having the formula wherein R and R are selected from the group consisting of methyl, phenyl, tolyl and xylyl, and about 15-100 parts per million of the ,B-hydroxyethyl ethylenediamine amides of oleic acid.

4. The gasoline composition of claim 2 wherein said phosphate has up to 2 methyl ester groups.

5. The gasoline composition of claim 3 wherein said phosphate has up to 2 methyl ester groups.

'6. Gasoline containing by weight from about 220 to about 440 parts permillionof a mixture comprising about 80 percent by weight of dimethyl xylyl phosphate and approximately 20 percent by weight of methyl dixylyl 5 phosphate, and about 15 to 50 parts per million of the 9- hydroxyethyl ethylenediamine amides of oleic acid.

References Cited in the file of this patent UNITED STATES PATENTS 2,080,299 Benning et a1 May 11, 1937 2,089,212 Kritchevsky Aug. 10, 1937 2,167,867 Benning Aug. 1, 1939 6 Rocchini July 22, 1952 Barusch et a1. June 17, 1958 Gaston July 15, 1958 Cantrell et a1. Sept. 9, 1958 Westlund Oct. 14, 1958 Cantrell et al. Dec. 2, 1958 FOREIGN PATENTS Great Britain Apr. 2, 1948 UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent N0. 3,035,906 May 22, 1962 James B. Hinkamp It is hereby certified that error appears in the above numbered patent requiring correction and that the said Letters Patent should read as corrected below.

Column 2, lines 19 to 24, the formula should appear as shown below instead of as in the patent:

C 1 waif 5 CH CH CH OH Signed and sealed this 4th day of September 1962.

(SEAL) Attest:

ERNEST W. SWIDER DAVID L. LADD Attesting Officer Commissioner of Patents 

1. A FUEL ADDITIVE COMPOSITION CONSISTING ESSENTIALLY OF A PHOSPHATE HAVING THE FORMULA 